1. Field of the Invention
The present invention relates to a power line communication device for a vehicle, which superimposes various signals on a power line so as to establish communication between devices equipped in the vehicle.
2. Description of the Related Art
These days, many technical advantages are offered to vehicles and therefore a vehicle has a plurality of electronic control units (hereinafter called “ECU”) on board. The ECUs control power windows, lamps and side mirrors as well as an engine and a transmission. The ECUs are connected with each other via private signal lines or common data buses and communicate with each other so that the ECUs operate cooperatively with each other.
Recently, the signal lines interconnecting the ECUs have been increased because the number of the ECUs has become larger and the number of signals has become larger due to complicated control. Thereby a structure of a wiring harness for a vehicle has become complex.
For solving the problem, a related art in which signals are superimposed on a supply voltage supplied to the respective ECUs via power lines so as to establish communication is disclosed in Japanese Patent Application Laid-open H07-50619.